DLC question DE gamer with UK games and US psn account

yes yes I know...
complicated, why am I using an American psn account as my main profile while living in Germany...
to be honest I forgot, I think it was something to do with the psn language setting etc...
but who knows..

Anyways, for the last year I have been getting games from the UK because they are in English, uncut and usually cheaper than their German versions.

My question is...
I was thinking of maybe getting the Dead space 3, Dishonoured and Bioshock infinite DLCs
(yes I know the DS3 one got crappy reviews..) do I need to get these from the UK psn store?
or can I use the DE store which would be easier (for the UK one I would need to buy UK credits on ebay)

I am asking since a while back (on my now defunct 360) I bought DLC from the German store for my UK game and suddenly I had characters speaking in German (with no way to change it)